Hinge stay mechanism



" Nov. 15, 1966 D. w. BIRMINGHAM ETAL 3,285,547

HINGE STAY MECHANISM Filed Oct. 1, 1964 1X 1x FIGS U20 fr* 16' 16 FIGB E19 /NVENToRs Doue/ Hs h//LL/HM /nM//vG/m/v.

PAUL Ufa/9L ROGER FER/vere@ face-to-face engagement.

United States Patent O 3,285,647 HINGE STAY MECHANISM Douglas WilliamBirmingham, Ickenham, Paul Carl Roger Fernberg, Farnham Common, andClifford Alexander Seckerson, Iver Heath, England, assignors toUnited-Carr Incorporated, Boston, Mass., a corporation of Delaware FiledOct. 1, 1964, Ser. No. 400,832 Claims priority, application GreatBritain, Oct. 9, 1963,

39,832/ 63 5 Claims. (Cl. 292-263) This invention relates to a lockingstay mechanism and, more specifically, to an improvement in ormodification of a locking stay mechanism described and claimed in myU.S. Patent No. 3,141,694.

Two embodiments of a locking stay mechanism according to the presentinvention are illustrated in the accompanying drawings, in which:

FIGURES l to 5 are plan views of separate parts of a first embodiment ofthe mechanism,

FIGURE 6 is a sectional view of the assembled mechanism of which theparts are shown in FIGURES 1 to 5, the section being taken on linesVI-VI of the respective parts shown in FIGURES l, 2 and 4,

FIGURE 7 is a sectional view, generally similar to FIGURE 6, of anassembled second embodiment of the invention, and

FIGURES 8 and 9 are respectively a plan View and a sectional View (takenon the line IX-IX of FIGURE 8), on an enlarged scale, of a pawlcomprised by the assembly shown in FIGURE 7.

The rst illustrated locking stay mechanism comprises an arm member 11,shown in FIGURE l, and a bracket member 12, shown in FIGURE 2, thesemem-bers being formed each with a hole 11 or 12 respectively by means ofwhich they can be pivotally secured together in sliding The members 11and 12 are further provided, adjacent their holes 11 and 12respectively, with slots 13 and 14 respectively adapted to receive adouble-ended pawl 15 (shown in FIGURE 3) with the thickness thereofaccommodated partly in the slot 13 and partly in the slot 14. As shownin FIGS. 2 and 3, slots 13 and 14 extend around the generally circularareas about the common pivotal axis of the arms 11 and 12. Each of theslots 13 and 14 has portions extending in the direction of relativepivotal movement, i.e. arcuately. These extensions overlie one anotherand accommodate the pawl 15. As the tirst arm is pivoted clockwiserelative to the other, the pawl 15 remains stationary relative to theother arm until its end is engaged by a portion of the wall of the slotof the lirst arm. The first arm carries the pawl 15 until the other endof the pawl engages a wall portion of the slot of the other arm; andwhen this occurs the two slot wall portions acting obliquely on oppositeends of the pawl 15, cam those ends in opposite directions and rotatethe pawl 15 clockwise into a first rotated position in which furtherrotation of the pawl is prevented by abutments of the ends of the pawlagainst stops formed on the wall of the slots 13 and 14.

If, now, the first arm is pivoted in a reverse direction relative to theother arm, the pawl 15 will remain stationary relative to the arm whichis not moving until the pawls forward end is engaged in a corner of theslot on the first arm. When this occurs, the other end of the pawl hasalready been disengaged by the wall portions of the slot of the armwhich is not moving. As the rst arm continues its reverse pivotalmovement the engagement of the pawl by the corner of the slot of themoving member carries the pawl bodily in a reverse direction also `anddue to the frictional strength on the pawl tends to locate it stillfurther in a clockwise direction, thereby roice tating the pawl into asecond rotated position. If the frictional restraint is not sufficient,then a camming action will take place similiar to that mentionedhereinbefore.

The slot 14 is closed at one face of the member 12 (namely the facewhich, in the assembled mechanism does not engage the member 11) -by acover 14 and according to the present invention this is achieved byproviding that, -when the slot 14 is punched out of the member 12 bymeans of a suitably shaped punch die, the punch does not completelyremove the material displaced in forming the slot 14 but leaves itperipherally integral with the member 12 to constitute, itself, thecover 14 in the manner indicated in FIGURE 6.

The mechanism also includes a boss 16, shown in FIGURE 4 and preferablymoulded from a plastic material such as polyethylene. The Iboss 16 isformed with a central hole 16 and with a projecting arm 17 from whichprojects a spigot 18. Further, the boss 16 is formed with a semi-annularrecess 19 which in the assembled mechanism accommodates Ia spring 20which is shown in FIGURE 5. The spring 20 is formed from an annularblank of sheet metal by bending the blank along a diameter thereof toprovide two mutually integral semi-annular parts overlying one anotherin spaced relationship.

In the assembled hinge stay mechanism, as shown in FIGURE 6, the partsare held together by a rivet 21 passed through the holes 16', 11 and 12before having its end 22 deformed. The lspigot 18 is located in a hole18 (see FIGURE 2) formed in the bracket member 12, thus preventingrelative rotation, about the bolt 21, between the bracket member 12 andthe boss 16. The pawl 15 (not shown in FIGURE 6, because in theillustrated relative position of the parts it would be approximately inthe positions, relative to the members 11 and 12, shown in broken linesin FIGURES 1 and 2 respectively) has its thickness accommodated partlyin the depth of the slot 14 and partly in the depth of the slot 13.

The spring 20, accommodated in the recess 19 of the boss 16, bearsagainst one flat face of the pawl 15 and urges its other flat faceagainst the cover 14. Since the boss 16 and bracket member 12, and thusthe spring 20 and cover 14 have no pivotal movement relative to oneanother, the pawl 15 tends because of friction between it and the spring20 and cover 14 to remain stationary relative to the bracket member 12and moves relative thereto only when constrained to do so by engagementwith wall portions of the slot 13 as the arm member 11 is pivotedrelative to the bracket member 12. It will be appreciated that the slots13 and 14 are so shaped and disposed relative to the holes 11 and 12respectively that, however the pawl 15 may be constrained to move in theslots, it remains engaged by the spring 20.

The second illustrated embodiment of the invention, shown assembled inFIGURE 7, differs from that described above only to the extent mentionedbelow; and the same reference numerals are used herein to refer tocorresponding parts in the two embodiments. Firstly, the materialpunched out in forming the sl-ot 13 in the member 11 is not completelyremoved but is left (in the same way as is described above withreference to the slot 14 of the member 11) peripherally integral withthe member 11 to -constitute a cover 13' for the slot 13. Accordingly noboss corresponding to the boss 16 is provided, and the members 11 :and12 are riveted together by means of a shorter rivet 21. The spring 20 isalso omitted, and instead of the pawl 15 shown in FIGURE 3 there isprovided in the slots 13 and 14 a pawl 15' which has the same shape butis provided at its centre (as shown in FIGURES 8 land 9) with a stoppedbore 22 in which is disposed a spring 23 surrounded by a cylindrical cap24 which the spring 23 urges out of the bore 22.

As in FIGURE 6 the pawl 15 is not shown, so in FIGURE 7 the pawl 15cannot be seen. It is housed, however, within the slots 13 and 14 withits thickness accommodated partly in the one slot and partly in theother, and with the projecting end of the cap 24 and the face of thepawl which is remote therefrom pressed by the spring 23 into frictionalengagement with the covers 13 and 14 respectively.

The pawl 15 co-operates with the slots 13 and 14, in operation of thesecond embodiment described above, in the same manner as the pawl 15,and to the same effect; and, so far as the operation of the mechanismsis concerned, it is not significant that, whereas the two flat surfacesofthe pawl 15 bear frictionally against the cover 14 and, respectively,the spring which is substantially secured against rotation relative tothe cover 14', the cap 23 and the flat face of the pawl 15 which isremote therefrom bear frictionally against two surfaces (namely thecovers 13 and 14') which pivot, relative to one another, about the rivet21'.

What we claim is:

1. A locking stay comprising a first member and a second memberconnected together by connecting means which permits, between themembers, a defined relative movement in a forward and a reversedirection, each member being formed with a surface overlying a surfaceof the other member and movable thereover during said relative movementof the members, the said surface of at least one of the members beingone side of a sheet-like portion of that member, and each of the saidsurfaces being formed with a slot partially overlying and in registerwith the slot of the other surface, the slot formed in the said surfaceof the said one member being formed by punching out a piece of thematerial of the said sheetlike portion and the said piece beingincompletely punched out and being peripherally integral with theremainder of the sheet-like portion, thereby constituting a cover forthe slot of the said one member, there being provided, yieldinglyconstrained to maintain its instantaneous position but otherwisefloating, a double-ended pawl having its thickness accommodated partlyin one slot and partly in the other slot, the slots being formed withbounding walls so shaped that on successive relative movements of themembers alternately in the forward direction and in the reversedirection the pawl is cammed by the walls successively intoprogressively rotated positions, the pawl being engaged by the walls ofthe two slots, in a rst and a third of said rotated positions, toprevent further relative movement of the members in the forwarddirection and, in the second of said rotated positions, to preventfurther relative movement in the reverse direction, and the pawl, in thefourth of its said rotated positions, being generally aligned with thepermitted direction of relative movement and with an extension in thatdirection of at least least one of the slots, said extension permittingmovement of the extended slot and of the associated member relative tothe aligned pawl and the other member, in the reverse direction to -arelative position of the members which is substantially displaced, inthe reverse direction of relative movement, from their relative positionas limited, in that direction, by the pawl in its said second rotatedposition.

2. A locking stay as claimed in claim 1, in which both the said memberscomprise sheet-like portions and the said surfaces are each one side ofthe said sheet-like portion of the said one member and of the othermember respectively and in which the slot formed in the said surface ofthe said other member is formed as an aperture extending right throughthe said sheet-like portion thereof, wherein there is provided againstthat side of the sheetlike portion of the said other member which isthen more remote from the said one member a non-integral covertherefore, and means securing the said non-integral cover in xedposition relative to the said one member.

3. A locking stay as claimed in claim 2, wherein the said non-integralcover is formed with a recess and there is provided in the recess springmeans which bears against the pawl `and urges it against theincompletely punchedout piece which constitutes the cover for the slotof the rst member, thereby yieldingly constraining the pawl to maintainits instantaneous position.

4. A locking stay as claimed in claim 1, in which both the said memberscomprise sheet-like portions and the said surfaces are each one side ifthe said sheet-like portions of the said one member and of the othermember respectively, wherein the slot formed in the said surface of thesaid other member is formed by punching out a piece of the material ofthe said sheet-like portion of the said other member and the said pieceis incompletely punched out and is peripherally integral with theremainder of the said sheet-like portion, thereby constituting a coverfor the slot of the said other member.

5. A locking stay las claimed in claim 4, wherein the pawl has one atface which bears slidingly against one of the said pieces constitutingcovers for the slots and is formed with a recess, there being providedwithin recess of the pawl spring means which projects therefrom andbears against the other of the said pieces, the said pieces and the saidspring means thereby yieldingly constraining the pawl to maintain itsinstantaneous position.

References Cited by the Examiner UNITED STATES PATENTS 2,048,725 7/1936Bartmore 16-191 2,566,182 8/1951 Flynn 292-267 3,141,694 7/1964Birmingham 16-139 FOREIGN PATENTS 4,693 1879 Great Britain. 355,556 8/1931 Great Britain. 594,981 11/ 1947 Great Britain.

EDWARD C. ALLEN. Primary Examiner.

RICHARD E. MORE, Examiner.

1. A LOCKING STAY COMPRISING A FIRST MEMBER AND A SECOND MEMBERCONNECTED TOGETHER BY CONNECTING MEANS WHICH PERMITS, BETWEEN THEMEMBERS, A DEFINED RELATIVE MOVEMENT IN A FORWARD AND A REVERSEDIRECTION, EACH MEMBER BEING FORMED WITH A SURFACE OVERLYING A SURFACEOF THE OTHER MEMBER AND MOVABLE THEREOVER DURING SAID RELATIVE MOVEMENTOF THE MEMBERS, THE SAID SURFACE OF AT LEAST ONE OF THE MEMBERS BEINGONE SIDE OF A SHEET-LIKE PORTION OF THAT MEMBER, AND EACH OF THE SAIDSURFACES BEING FORMED WITH A SLOT PARTIALLY OVERLYING AND IN REGISTERWITH THE SLOT OF THE OTHER SURFACE, THE SLOT FORMED IN THE SAID SURFACEOF THE SAID ONE MEMBER BEING FORMED BY PUNCHING OUT A PIECE OF THEMATERIAL OF THE SAID SHEETLIKE PORTION AND THE SAID PIECE BEINGINCOMPLETELY PUNCHED OUT AND BEING PERIPHERALLY INTEGRAL WITH THEREMAINDER OF THE SHEET-LIKE PORTION, THEREBY CONSTITUTING A COVER FORTHE SLOT OF THE SAID ONE MEMBER, THERE BEING PROVIDED, YIELDINGLYCONSTRAINED TO MAINTAIN ITS INSTANTANEOUS POSITION BUT OTHERWISEFLOATING, A DOUBLE-ENDED PAWL HAVING ITS THICKNESS ACCOMMODATED PARTLYIN ONE SLOT AND PARTLY IN THE OTHER SLOT, THE SLOTS BEING FORMED WITHBOUNDING WALLS SO SHAPED THAT ON SUCCESSIVE RELATIVE MOVEMENTS OF THEMEMBERS ALTERNATELY IN THE FORWARD DIRECTION AND IN THE REVERSEDIRECTION THE PAWL IS CAMMED BY THE WALLS SUCCESSIVELY INTOPROGRESSIVELY ROTATED POSITIONS, THE PAWL BEING ENGAGED BY THE WALLS OFTHE TWO SLOTS, IN A FIRST AND A THIRD OF SAID ROTATED POSITIONS, TOPREVENT FURTHER RELATIVE MOVEMENT OF THE MEMBERS IN THE FORWARDDIRECTION AND, IN THE SECOND OF SAID ROTATED POSITIONS, TO PREVENTFURTHER RELATIVE MOVEMENT IN THE REVERSE DIRECTION, AND THE PAWL, IN THEFOURTH OF ITS SAID ROTATED POSITIONS, BEING GENERALLY ALIGNED WITH THEPERMITTED DIRECTION OF RELATIVE MOVEMENT AND WITH AN EXTENSION IN THATDIRECTION OF AT LEAST LEAST ONE OF THE SLOTS, SAID EXTENSION PERMITTINGMOVEMENT OF THE EXTENDED SLOT AND OF THE ASSOCIATED MEMBER RELATIVE TOTHE ALIGNED PAWL AND THE OTHER MEMBER, IN THE REVERSE DIRECTION TO ARELATIVE POSITION OF THE MEMBERS WHICH IS SUBSTANTIALLY DISPLACED, INTHE REVERSE DIRECTION OF RELATIVE MOVEMENT, FROM THEIR RELATIVE POSITIONAS LIMITED, IN THAT DIRECTION, BY THE PAWL IN ITS SAID SECOND ROTATEDPOSITION.